We're dividing 21021259 by 203 
We want to figure out the number of times 21021259 can be divided by 203.

Moving on to step 1:
2 divided by 203 is 0 with a remainder of 2.
Write down 0 as next digit of the result. 
Result so far: 0.0
If we subtract 0 from 2, we get 2.
Take the next digit (1) from the dividend and append it to 2, then repeat: 21 / 203

Step 2:
203 goes into 21 0 times with a remainder of 21.
The next digit of our result is 0. 
Result so far: 0.0
If we subtract 0 from 21, we get 21.
Fetch the next digit (0) from the dividend, attach it to 21 and continue: 210 / 203

Advancing to step 3:
The number 203 fits into 210 1 times, leaving a remainder of 7.
The number 1 becomes the next digit in our result. 
Result so far: 1.0
The remainder is 7 after subtracting 203 from 210.
Include the next digit (2) from the dividend after 7, then repeat: 72 / 203

Advancing to step 4:
The number 203 fits into 72 0 times, leaving a remainder of 72.
The next digit of our result is 0. 
Result so far: 10.0
If we take 0 away from 72, we end up with 72.
Append the next digit (1) from the dividend to 72 and continue with: 721 / 203

Moving on to step 5:
If we divide 721 by 203, we get 3 and a remainder of 112.
The number 3 becomes the next digit in our result. 
Result so far: 103.0
If we take 609 away from 721, we end up with 112.
Fetch the next digit (2) from the dividend, attach it to 112 and continue: 1122 / 203

Going ahead to step 6:
203 goes into 1122 5 times with a remainder of 107.
Record the quotient 5 as the next digit in the result. 
Result so far: 1035.0
Deduct 1015 from 1122 and we're left with 107.
Grab the next digit (5) from the dividend, add it to 107, then carry on: 1075 / 203

On to step 7:
The number 203 fits into 1075 5 times, leaving a remainder of 60.
Record the quotient 5 as the next digit in the result. 
Result so far: 10355.0
If we subtract 1015 from 1075, we get 60.
Append the next digit (9) from the dividend to 60 and continue with: 609 / 203

Step 8:
The number 203 fits into 609 3 times, leaving a remainder of 0.
Put 3 as the next digit of the answer. 
Result so far: 103553.0
Subtracting 609 from 609 leaves us with 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Let's proceed to step 9:
The number 203 fits into 0 0 times, leaving a remainder of 0.
Write down 0 as next digit of the result. 
Result so far: 103553.0
If we take 0 away from 0, we end up with 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Advancing to step 10:
When dividing 0 by 203, we get 0 with a remainder of 0.
The next digit of our result is 0. 
Result so far: 103553.0
Subtracting 0 from 0 leaves us with 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Our division results in 103553.0 with a remaining 0.0.